Pallet rack for Material Handling Systems

Pallet Rack Types

Many types of pallet racks are available with different designs to fulfill specific functions or create specific advantages. When deciding on the type of pallet rack to use, several basic considerations have to be taken into account:
 -Desired storage density
 -Floor space and building height
 -Inventory accessibility
 -Inventory rotation
 -Item/load size and weight
 -Optimal storage design
 -Cost of materials and installation

Some of the most common types of pallet rack systems used include:

Selective pallet rack systems are the most commonly used rack system because they are inexpensive and quick and easy to assemble. Selective pallet racks typically come in two configurations: a teardrop, or clip-in configuration, and a structural bolt-together configuration. The nickname “teardrop” comes from the fact that the holes on the column of the upright are shaped like a teardrop. Pallets then rest on the horizontal beams that are held in place by mounting clips.

Because the clips on teardrop configurations can be quickly moved, the shelves can be easily adjusted to different heights to accommodate various load sizes. This is convenient for a warehouse that needs to store a wide variety of product sizes. Another advantage of selective pallet rack systems is the easy accessibility they provide to all products at all times. Such accessibility is important if the inventory is rapidly depleted and restocked (called quick turnover). A selective pallet rack system is commonly used in a “big-box” distribution application, as well as in retail store inventory rooms, cold storage applications, wholesale stores, etc.
Structural pallet rack systems are very similar to selective pallet rack systems, but the horizontal supports are attached to the uprights with bolts and often have an increased weight-bearing capacity. Also, structural pallet racking can be designed into the structure of the building itself, so that the upright columns are simultaneously used to support the roof of the storage facility, in which case the structural pallet rack uprights replace the storage building’s vertical support I-beams.

Very Narrow Aisle (VNA) is the use of selective pallet racking in a tighter configuration to provide maximum space utilization within a storage facility. These systems typically operate in conjunction with wire-guided or rail-guided reach-truck systems. A wire-guided system consists of a wire embedded in the concrete floor that provides tracking for the reach-truck. A rail-guided system consists of angle iron bolted to the floor down the length of each row. Typically, the angle iron is 4” by 3” and ¼” - ⅜” inches thick.

Push-back pallet rack systems are designed around the principle of organizing space by depth rather than width. This depth arrangement greatly reduces aisle space and increases storage density. In this configuration, each row is multiple pallets deep, and often has wheeled carts that fit onto rails to take advantage of gravity, saving enormous amounts of energy for moving heavy pallets. When a forklift sets the pallet onto the cart, it drives forward and causes the pallet to bump the next pallet, causing the entire row of pallets to roll backwards. When removing a pallet from the front position the remaining pallets immediately stage themselves forward so that the next available pallet can be accessed.

Pallet Flow and Carton Flow is a pallet racking system also designed for depth space; it uses a slightly inclined conveyor that makes pallets or totes move easily along a sloped plane. These systems are also called gravity flow or dynamic flow racking systems. The pallet flow system often has complex motion and braking systems to control the speed of the moving pallet.

Drive-in and Drive-through (sometimes spelled Drive-thru) are storage rack configurations that allow the forklift to drive directly into the lane of stacked rows (called a bay). The difference between a drive-in and a drive-thru pallet rack system is simply whether the bays have an entry at only one end, or at both ends. Drive-in rack systems use a common entry and exit, while drive-thru systems have entry points at either end of the bay. Because a drive-in racking system has only one entrance, it uses what is called a “Last In, First Out” (LIFO) storage method. With only one entrance, the last pallet put into a row is necessarily the first one to be taken out. A drive-thru storage system, with two different entry points, can also use a “First-In, First-Out” (FIFO) storage method. With a FIFO system, pallets are loaded in one end and are pushed back to the other end, where they are then at the front of the row on the opposite side. The first pallet put into such a row is the first one taken out at the other end. This system is advantageous for material with an expiration date or wherever shelf life is a major concern.

Some of the disadvantages of the push-back, drive-in, and drive-thru systems are less access to all stock at any given moment (although if the stored product is all the same, it should not matter), and that such arrangements are more expensive than the simpler selective pallet rack storage systems. In large factory production facilities, however, push-back pallet rack systems are essential, since the efficiency of time and space is optimized.

RackSmart currently has used, heavy duty pallet rack uprights and beams in Memphis, Tennessee, used pallet rack uprights and beams in Savannah, Georgia, used pallet rank uprights, beams and wire decks in Elberton, Georgia, and used pallet rack and drive-in racks in Lebanon, Indiana. Need used pallet rack in California, no problem. Don’t just look for used pallet rack and storage systems in your county, call RackSmart and let us do the search for you.  We can find used pallet rack in your local county or state area for you, or we can ship pallet rack and warehouse storage systems to any place in the country, any county or city. We also provide pallet rack and installation services to Jamaica, Belize and other parts of the Caribbean.  All of our metal storage racks are made of the finest steel and are in excellent used or refurbished condition. Call RackSmart Inc. 706-213-630.